Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
We quantitatively assess the impacts of Downgrading Protected Areas (PAD) on biodiversity in the U.S. Results show that PAD events significantly reduce biodiversity. The proximity to PAD events decreases the biodiversity (abundance) by 26.0 % within 50 km compared with records of species further away from the PAD events. We observe an overall 32.3 % decrease in abundance after those nearest PAD events are enacted. Abundance declines more in organisms living in contact with water and non-mammals. Species abundance is more sensitive to the negative impacts in areas where the decisions of PAD events were later reversed, as well as in areas close to protected areas belonging to the International Union for Conservation of Nature (IUCN) category. The enacted PAD events between the period 1903 to 2018 in the U.S. led to economic losses of approximately $689.95 million due to the decrease in abundance. Our results contribute to the understanding on the impact of environmental interventions such as PAD events on broadscale biodiversity change and provide important implications on biodiversity conservation policies.